Device for Stretching the Skin

ABSTRACT

In a device for stretching the skin, particularly for closing a wound, anchoring elements are anchored in the skin. The anchoring elements are movable on a guide device. First anchoring elements are anchored in the skin of the edge of the wound. Second anchoring elements are adjustable on the guide device in the stretching direction behind the first anchoring elements in relation to and independently of said first anchoring elements

The invention relates to a device for stretching the skin.

Skin stretching is used in surgical practice to obtain skin fortransplantation and in particular for closing large-area wounds bypulling together the edges of the wound.

DE 44 44 130 A1 discloses moving two anchoring elements on guide railsrunning in the direction of the desired stretching of the skin by meansof a threaded spindle, the anchoring elements being movable in anadjustable fashion. The anchoring elements are formed by flanges bearinghooks that may be inserted into the skin. The hooks of both anchoringelements are inserted into the opposing edges of a wound in such a waythat the wound is located in the intermediate area between the anchoringelements. If the anchoring elements are moved opposite one another, thenthe edges of the wound are pulled together. The tensile force acting onthe skin of the edges of the wound leads to an increased proliferationof tissue, which benefits and allows the pulling together of the woundedges.

U.S. Pat. No. 4,896,680 discloses a device in which a flexible bandribbed in a transverse manner serves as a guide device. The one end ofthe band is fixed in the skin by means of an anchoring element in theform of a safety needle. A second such anchoring element is guided onthe band in an adjustable manner and locked in the transverse ribs ofthe band.

U.S. Pat. No. 5,571,138 discloses the use of a flexible band as a guidedevice for obtaining skin for transplantation, with two anchoringelements being disposed on the band in an adjustable and clampablemanner in order to stretch the skin on both sides of the intermediatearea between these anchoring elements and to obtain excess skin fortransplantation in the intermediate area.

U.S. Pat. No. 5,531,790 discloses a baldness treatment in which the skinwith hair on the sides of the head is stretched and pulled together by adevice comprising an elastic band that carries one or more rows of hooksas anchoring elements on both ends. The hooks are inserted into the skinon the head with hair such that said skin is pulled together by theelasticity of the band. By arranging multiple rows of anchoringelements, it is possible for larger skin regions to be captured andstretched. The anchoring elements are not provided in an adjustablefashion.

The object of the invention is to create a device for stretching theskin that allows an improved effectiveness of skin proliferation.

This object is attained according to the invention by a device havingthe features recited in claim 1.

Advantageous embodiments of the invention are listed in the subordinateclaims.

In the device according to the invention, a pair of first anchoringelements are anchored in the skin. These first anchoring elements areguided opposite one another in an adjustable fashion, whereby thedistance between the first anchoring elements and the intermediate areabetween these anchoring elements is reduced. The skin is stretched onboth sides outside of the first anchoring elements. In the most commonapplications for wound closure, the edges of the wound are pulledtogether in order to reduce the wound area located between the anchoringelements and to stretch the skin areas adjacent to the edges of thewound.

The tensile force that may be exerted on the skin by these firstanchoring elements is limited. If the tensile force is too great, theanchoring elements may tear out of the skin. Even if the anchoringelements do not tear out, it is possible for such a high pressure to beexerted on the skin tissue located in front of the anchoring elementsthat the skin becomes ischemic and, if the tensile force is maintainedfor a longer period, becomes necrotic.

The invention counteracts this disadvantage in that at least one secondanchoring element is disposed behind at least one of the first anchoringelements in the pull direction. This second anchoring element is alsoanchored in the skin and, due to its arrangement, is located at agreater distance from the intermediate area between the first anchoringelements, for example, from the edge of the wound. The at least onesecond anchoring element is also adjustable on the guide element. Byvirtue of their adjustability, the second anchoring elements are able toexert an adjustable tensile force on the skin that is effective at agreater distance from the edge of the wound. This results in thefollowing significant advantages for skin stretching.

Experimental investigations have shown that the tensile force acting onthe skin only has a small range. By virtue of the elasticity of theskin, the tensile force dissipates over a stretch of a few centimeters,such that, in human skin, the tensile force generally has no more effectat a distance of 5 or 6 centimeters from the introduction of the tensileforce and does not stimulate any tissue proliferation. Using one or moresecond anchoring elements, an additional tensile force is exerted on theskin at a correspondingly greater distance from the edge of the woundsuch that a significantly greater skin area may be used for stretchingand tissue proliferation.

By means of the second anchoring elements, the skin is already placedunder tensile force before the first anchoring element such that theskin that has been pre-stressed by the second anchoring elements needsonly to be loaded with a relatively low tensile force by the last firstanchoring element in the pulling direction. Therefore, only a low levelof force is acting on the skin at each anchoring point due to theindividual anchoring elements and particularly due to the firstanchoring elements. This prevents the first anchoring elements fromtearing out. The pressure exerted by the first anchoring elements on theskin tissue before these anchoring elements may be reduced under theischemic threshold without impeding tissue proliferation. Skinstretching may therefore also be conducted over a long period of timewithout damage to the tissue, which results in a quicker and moreeffective treatment.

The tensile force introduced into the skin by the anchoring elements maybe selected to be large enough that ischemia results on the pressureside of the anchoring elements. Before the ischemia tolerance of thetissue is reached, i.e., at the latest after a few hours, the tensileforce must be lifted, or at least reduced far enough that blood flow tothe tissue is once again possible on the pressure side of the anchoringelement. In such a cyclical stretching, temporal regeneration intervalsduring which the skin is not stretched are placed between the intervalsof stretching and thus stimulation of tissue proliferation.

Because the first and second anchoring elements may be adjustedindependently of one another on the guide device, the tensile forcesworking on the skin via the first and second anchoring elements may alsobe varied independently of one another. For example, individualanchoring elements may be set to a high tensile force, which causes astrong degree of proliferation, said anchoring elements optionallyexceeding the ischemic threshold on the pressure side of the anchoringelements. At the same time, the tensile force is reduced for the otheranchoring elements in such a way that the skin tissue before theseanchoring elements is again able to recover with good blood perfusion.In corresponding time cycles, the function of the anchoring elements isinterchanged, such that the skin tissue that was previously under a highdegree of tensile stress is able to recover, and the tensile force isexerted via the anchoring elements that were previously relaxed. Becausesome of the anchoring elements are always exerting a high degree oftensile force on the skin, the skin is constantly under a high degree oftensile force that is advantageous for tissue proliferation withoutcausing damage to the tissue. The introduction of this high degree oftensile force into the skin changes its position in a cyclical manner.

In wound treatment, situations may also occur in which the skin shouldbe stretched only in the region of one edge of the wound, whilestretching of the skin on the opposite edge of the wound is not desired,for example, because the edge of a bone is located below this edge ofthe wound. In such a situation, the device according to the inventionmay be advantageously used in that, on the edge of the wound where noskin stretching is to occur, the first anchoring element and subsequentsecond anchoring elements are anchored in the skin and adjusted on theguide device such that the second anchoring elements do not exert anytensile force on the skin. Here, the second anchoring elements onlyserve to fix the device on the one side of the wound in a large-area ofthe skin without stretching the skin in order to support the tensileforce acting on the other edge of the wound for the purpose ofstretching the skin.

The guide device, the anchoring elements, and the adjustment of theanchoring elements on the guide device may be embodied in differentways. It is essential that the anchoring elements be adjustable on theguide device and be held in their respective adjusted position in orderto be able to adjust and maintain the respective tensile force of theindividual anchoring element in an individual fashion. The guide devicemay be made of rigid guides or a flexible band. The anchoring elementsmay be hooks that are insertable into the skin and be disposedindividually or in rows in the anchoring elements. The anchoringelements may also be anchored in the skin in the form of safety needles.The tensile force exerted by the anchoring elements on the skin may beinduced by the positional adjustment of the anchoring elements and thusby the stretching of the skin against its elasticity. In addition,spring forces may also reinforce and influence the tensile force.

The adjustment of the anchoring elements may occur manually in a simplefashion, for example, in accordance with a predetermined timetable or inaccordance with a current evaluation of the skin and wound situation. Itis also possible for the adjustment of the anchoring elements to becaused by motorized drive systems. Such drive systems may be controlledaccording to a predetermined or programmable plan in a temporal fashionor with regard to the respective tensile force. Finally, a regulatedautomatic adjustment of the anchoring elements is possible. To this end,it is preferably for the tensile force introduced into the skin by eachof the anchoring elements to be measured, which is a function of theskin stretching currently occurring, and for the tensile force of theanchoring elements to be regulated to a target value that may bepredetermined. Thus, an optimization of skin distraction is possibleover longer periods of time without effort by personnel.

The invention shall be described in greater detail in the following withreference to exemplary embodiments shown in the drawings, which show:

FIG. 1 a side view of a device for stretching the skin in a firstembodiment,

FIG. 2 a view of the device according to FIG. 1 from below,

FIG. 3 a view from below of a modification of this device,

FIG. 4 a view from below of an additional modification of this device,

FIG. 5 a detail of the device of the first embodiment in a verticalsection,

FIG. 6 a view of the detail from FIG. 5 from the top,

FIG. 7 a view of a second embodiment of the device from the top, and

FIG. 8 an exemplary use of the device.

In the first exemplary embodiment of FIGS. 1 and 2, a device is shownfor stretching the skin. FIG. 1 shows one of the most important uses ofthis device, namely the stretching of the skin 10 at the edges of awound 12 in order to pull the skin 10 of the edges of the wound togetherand to close the wound 12.

The device has a guide device that is embodied as a flexible band 14 inthe exemplary embodiment shown in FIGS. 1 and 2 and is preferably madeof plastic. Anchoring elements 16 are disposed on the band 14. Theanchoring elements 16 may be fixed on the band 14 in the longitudinaldirection of the band 14 in their respective adjusted positions. Theanchoring elements 16 are designed such that they may be anchored in theskin 10.

In the exemplary embodiment shown, the anchoring elements 16 have hooks18 on their underside that are inserted into the skin 10 in order tohook and anchor the anchoring elements 16 into the skin 10. Otherdesigns of the anchoring elements are known as well and may be used asan alternative to the hooks 18. Preferably, the anchoring elements 16may also have anchors in the form of safety needles as is shown, forexample, in U.S. Pat. No. 4,896,680. In this embodiment, the anchoringelements 16 have a safety needle that is disposed transverse to thelongitudinal extension of the band 14 and is inserted into the skin 10.The advantage of a design of the anchoring elements 16 with hooks 18lies in the fact that the hooks 18 may simply be placed in the skin 10and may be arranged with a greater freedom of variation in thetransverse direction relative to the band 14. The advantage of anchoringelements 16 with a safety needle lies primarily in the fact that thisanchor in the form of a safety needle cannot be unintentionally releasedfrom its anchoring in the skin 10.

As is shown in FIGS. 1 and 2, two first anchoring elements 16.1 sit onthe band 14 and are inserted into the skin 10 opposite one another onthe opposite edges of the wound 12. The first anchoring elements 16.1may be slid relative to one another on the band 14 such that theirdistance from one another in the longitudinal direction of the band 14is reduced and the intermediate area between the first anchoringelements 16.1, in the present case the region of the wound 12, isreduced. The skin 10 forming the edges of the wound 12 is thus stretchedin the longitudinal direction of the band 14 such that the edges of thewound are moved toward one another in order to close the wound 12. Ifthe skin at the edges of the wound is stretched far enough that theopposing edges of the wound are touching, the edges of the wound may bestitched or clamped to one another in order to close the wound 12.

The stretching of the skin 10 induces an increased tissue proliferationin the region in which the skin 10 is stretched such that the stretchingof the skin 10 leads to an enlargement of the available skin area. Thegreater the tensile force exerted on the skin by the anchoring elements16, the greater the tissue proliferation. In conventional devices thathave only first anchoring elements 16.1 that are anchored in the skin 10of the edges of the wound, the tensile force acting on the skin islimited. The anchoring elements 16, for example, the hooks 18, exert apressure on their front side pointing in the pull direction on thetissue that corresponds to the tensile force applied. If this pressureexceeds the so-called ischemic threshold, this pressure hinderscirculation through the tissue. This ischemic state can only exist for alimited amount of time because otherwise the tissue will becomenecrotic. In the known devices, the tensile force must therefore be keptbelow the ischemic threshold, which results in a lesser degree of skinstretching and tissue proliferation, or the tensile force must beinterrupted at regular intervals for a recovery phase to allowcirculation through the tissue, which also reduces the effectiveness ofthe skin stretching. Finally, the range of the tensile forces introducedinto the skin is limited to a few centimeters. The tensile forceintroduced into the skin 10 via the anchoring elements 16 reducesexponentially with the distance from the anchoring element 16 and, inhuman skin, for example, has fallen to zero after approximately 5 or 6centimeters. This means that only a correspondingly limited area of skinis mobilized by the applied tensile forces and stimulated to producetissue proliferation.

In order to eliminate or reduce these problems, at least one secondanchoring element 16.2 is provided according to the invention inaddition to the pair of first anchoring elements 16.1. In the exemplaryembodiment shown in FIGS. 1 and 2, one second anchoring element 16.2 isassociated with each of the first anchoring elements 16.1. The secondanchoring elements 16.2 are preferably designed in the same fashion asthe first anchoring elements 16.1. The second anchoring elements 16.2may therefore also be slid on the band 14 and locked in their respectiveadjusted positions.

In FIG. 1, for example, a first anchoring element 16.1 has been insertedinto the skin 10 of the right-hand side of the wound 12. A secondanchoring element 16.2 is disposed on the band 14 on the side of thefirst anchoring element 16.1 facing away from the wound 12. This secondanchoring element 16.2 is anchored in the skin 10 at a distance from thefirst anchoring element 16.1 in the longitudinal direction of the band14. Corresponding to the range of the tensile forces in skin 10, thisdistance may be 1 to 20 cm depending on the application, for human skin,the distance is generally 1.5 to 3 cm. The second anchoring element 16.2exerts a tensile force on the skin 10 that is generated by theadjustment of the second anchoring element 16.2 on the band 14 againstthe wound 12, i.e., to the left in FIG. 1. In this manner, an additionalarea of skin to the right of the second anchoring element 16 determinedby the range of the tensile force is mobilized and stimulated togenerate tissue proliferation. In addition, the second anchoring element16.2 causes a preliminary tensing of the skin 10 for the first anchoringelement 16.1 disposed on the edge of the wound. Thus, a tensile forcethat can be determined by adjusting the first anchoring element 16.1relative to the second anchoring element 16.2 acts on the skin regionbetween the first anchoring element 16.1 and the second anchoringelement 16.2.

A corresponding arrangement of a first anchoring element 16.1 and asecond anchoring element 16.2 is shown in FIG. 1 on the left-hand sideof the wound 12. It is easily discernible that the second anchoringelement 16.2 may also be provided on only one side of the wound 12, suchthat only one single first anchoring element 16.1 is provided on oneside of the wound. In addition, it is easily discernible that more thanone second anchoring element 16.2 may also be disposed on one sidebehind the first anchoring element 16.1. If two or more second anchoringelements 16.2 are disposed one behind the other, then these secondanchoring elements are adjustable and lockable independently of oneanother in the longitudinal direction of the band 10 and their functionsadd up in the manner described above.

The device as shown in FIGS. 1 and 2 offers the following use optionsand advantages:

By virtue of the anchoring elements 16.1 and 16.2 disposed one behindthe other, it is possible to stretch larger areas of the skin in thedirection of the longitudinal extension of the band 14, i.e., in thestretching direction, and to activate tissue proliferation in thoseareas. Because a larger tissue area is being mobilized, a larger skinyield results for closing the wound 12 with the same tissueproliferation per area.

The second anchoring elements 16.2 generate a preliminary tension of theskin for the additional second anchoring elements 16.2 or the firstanchoring element 16.1 following in the pull direction. The tensileforce introduced into the skin at points by the individual anchoringelements 16.1, 16.2 may therefore be selected at a lower level. Evenwith a lower tensile force of the individual anchoring elements, astretching of the skin and skin yield may be obtained that is attainableusing conventional means only at a substantially higher level of tensileforce. Even if the force introduced by the individual anchoring elementslies below the ischemic threshold, an effective skin yield may beobtained.

In an additional use of the device according to the invention, thetensile forces introduced into the skin 10 via the first anchoringelement 16.1 and via the one or more second anchoring elements 16.2 maybe varied over time. For example, in a first time period, a high degreeof tensile force is introduced into the skin 10 via the first anchoringelement 16.1 that exceeds the ischemic threshold on the pressure side ofthe anchoring element 16.1. At the same time, the second anchoringelement 16.2 is exerting only a low level of tensile force on the skin10 or is completely relaxed. In a subsequent time period, the first andsecond anchoring elements exchange roles. The second anchoring element16.2 is set such that it introduces a very high level of tensile forceinto the skin 10, which may exceed the ischemic threshold on thepressure side of the second anchoring element 16.2. During this timeperiod, the tensile force introduced by the first anchoring element 16.1is reduced or completely eliminated. These periods then repeatthemselves cyclically. In this manner, a high level of tensile force isbeing introduced into the skin 10 via one of the anchoring elements 16.1or 16.2, which leads to a high degree of tissue proliferation. The otheranchoring element 16.1 or 16.2 is relaxed or relaxed to the extent thatthe tissue on the pressure side of the anchoring element again has goodand complete blood circulation and is able to regenerate. Overall,therefore, the skin 10 may be stretched with a very high degree oftensile force in an uninterrupted fashion for the entire duration oftreatment, with the contact points of these tensile forces changing in acyclical manner, such that the tissue is constantly able to regeneratesufficiently. Because the high degree of tensile force is constantlyacting on the skin 10 at different contact points, a very effectivestretching and tissue proliferation is attained.

FIG. 2 shows an embodiment in which each anchoring element 16.1, 16.2has two hooks 18 next to one another transverse to the longitudinaldirection of the band 14. Such an embodiment allows the introduction offorce into a relatively narrow section of the edge of the wound. In thecase of a larger wound 12, the edge of the wound may be stretched in anindividual fashion by a plurality of devices disposed one next to theother.

FIG. 3 shows a modification in which the anchoring elements 16.1, 16.2have larger dimensions transverse to the longitudinal direction of theband 14 and thus may also have a plurality of hooks 18. This embodimentis suitable for stretching a wider breadth of the edge of the wound.

FIG. 4 shows an additional modification in which two bands 14 areprovided running parallel to one another in the stretching direction, onwhich the respective anchoring elements 16.1, 16.2 are disposed in anadjustable and fixable manner. This embodiment provides a greater degreeof stability with broad anchoring elements 16.1, 16.2. In addition, theanchoring element 16.1, 16.2 may be adjusted differently with both ofits ends on the two bands 14. In this manner, the anchoring elements16.1, 16.2 may also be set diagonally against the direction of the bands14 and thus against the stretching direction, such that they may beadapted to the path of the edge of the wound.

FIGS. 5 and 6 show an exemplary embodiment of an anchoring element 16and its adjustability and fixability on the band 14. The flexible band14 has transverse ribs 20 on its top side that may, for example, form asaw profile. The anchoring element 16 has, for example, a housing 22made of plastic in the form of a box that surrounds the band 14. Hooks18 are injected on the underside of the housing 22. The housing 22 isguided on the band 14 with its underside and side walls. The upper sideof the housing 22 is designed with a locking tongue 24 that is preloadedagainst the top of the band 14. The locking tongue 24 rests against thetop of the band 14 with a locking nose. As may be seen from FIG. 5, thedesign of the transverse ribs 20 in the form of a toothed saw and of thelocking tongue 24 allows an adjustment of the anchoring element on theband 14 to the left. Here, the locking tongue 24 glides over thetransverse ribs 20. However, in FIG. 5, the anchoring element 16 islocked against a movement of the anchoring element 16 to the right onthe band 14 in that the locking tongue 24 is looked into the teeth ofthe transverse ribs 20 with its locking nose. A handling tip 26 on thefree end of the locking tongue 24 allows the locking tongue to be liftedout of the locking of the transverse ribs 20 against its elastic force,such that the anchoring element 16 may be released from its lockedposition and moved to the right on the band 14 in FIG. 5.

FIG. 7 shows another embodiment of the device. Insofar as thisembodiment corresponds to the embodiment described above, the samereference characters have been used and reference is made to the abovedescription.

In the exemplary embodiment according to FIG. 7, the guide device has athreaded spindle 28 on which the first anchoring elements 16.1 areadjustable opposite one another. The guidance of the first anchoringelements 16.1, the design of the threaded spindle 28, and theadjustability may be designed, for example, in the manner known from DE44 44 130 A1. Other embodiments lie within the scope of the actions ofthe skilled practitioner.

As is shown in FIG. 7 for only one side of the device, a secondanchoring element 16.2 may be connected to the first anchoring element16.1. The threaded rods 30 disposed on the outer ends of the anchoringelements 16.1 and 16.2 serve to connect and to guide the secondanchoring element 16.2 on the first anchoring element 16.1. The threadedrods 30 penetrate continuous bores in the anchoring elements 16.1 and16.2. The threaded rods 30 are held on the anchoring element 16.1 by ahead 32. A threaded nut 34 is screwed onto the opposite end that isguided through the second anchoring element 16.2. By adjusting thethreaded nut 34 on the threaded rod 30, the distance between the firstanchoring element 16.1 and the second anchoring element 16.2 may be setand fixed. In the stretching direction, i.e., in the direction of thethreaded rods 30, the anchoring elements 16.1 and 16.2 are held at theirdistance limited by the threaded nut 34 by the elastic tensile stress ofthe skin. Optionally, the anchoring elements 16.1 and 16.2 may still bekept adjacent to the head 32 and the threaded nut 34 by an additionalscrew pressure spring 36 sitting on the threaded rod 30. By adjustingthe threaded nuts 34 on the threaded rods 30, the second anchoringelement 16.2 may be pulled relative to the first anchoring element 16.1in order to adjust the tensile force introduced into the skin 10 by thesecond anchoring element 16.2. In so doing, the first anchoring element16.1 is supported via the threaded spindle 28 and the anchoring elementson the other side of the wound 12.

In a corresponding manner, additional second anchoring elements 16.2 maybe connected to the second anchoring element 16.2, as is shown in FIG. 7for an additional anchoring element 16.2. The connection and theadjustability between the consecutive second anchoring elements 16.2corresponds to the connection and adjustability between the firstanchoring element 16.1 and the second anchoring element 16.2.

An additional variant is shown for connecting and guiding the twoconsecutive second anchoring elements 16.2. A screw pressure spring 38is placed between the threaded nut 34 and the anchoring element 16.2.The screw pressure spring 38 presses the corresponding anchoring element16.2 in the pull direction of the device. The screw pressure spring 38thus determines the tensile force exerted on the skin 10 by theanchoring element 16.2. The screw pressure spring 38 may be providedwith initial tension by means of the threaded nut 34 for the purpose ofsetting this introduced tensile force. The screw pressure spring 38maintains this force introduced into the skin 10 via the anchoringelement 16.2 even over a certain movement path of the anchoring element16.2. Even when the skin 10 stretches under the effect of the introducedtensile force and the anchoring element 16.2 wanders on the threadedrods 30, the introduced tensile force is maintained by the screwpressure spring 38. Readjustment of the threaded nuts 34 in order toadjust the active tensile force therefore only becomes necessary overlonger time intervals.

The embodiment according to FIG. 7 clearly shows how, by the respectiveadjustment of the first anchoring elements 16.1 on the threaded spindle28 and the mutual adjustment of the anchoring elements 16.1 and 16.2 viathe threaded rods 30 and the threaded nuts 34, switching between apulling phase and regeneration phase is also possible by mutualadjustment.

If the device is designed in an essentially symmetrical fashion on bothsides of the wound 12, as is shown by embodiment described above, anadjustable tensile force is essentially exerted on the skin 10 on bothedges of the wound. The skin 10 is correspondingly stretched on bothedges of the wound.

However, there are cases in which the skin is to be stretched on onlyone side of the wound 12 to the greatest extent possible whilestretching of the skin is not desired on the other edge of the wound,for example, because pressure-exerting structures are located below thisregion of skin.

FIG. 8 shows such a case in which a wound 12 is located adjacent to theedge of a bone 40.

In this case, the device is anchored with a first anchoring element 16.1(and, optionally, with additional second anchoring elements 16.2 aswell) in the edge of a wound whose skin is to be stretched. On the sideof the wound where the skin 10 is not to be stretched, a first anchoringelement 16.1 and one or, preferably, more second anchoring elements 16.2are anchored in the skin 10. The distances between the first anchoringelement 16.1 and the subsequent anchoring elements 16.2 is not adjustedin this case, such that the skin 10 between the first anchoring element16.1 and the consecutive second anchoring elements 16.2 is not subjectedto any tensile force and is not stretched. The anchoring elements 16.2thus achieve an anchoring for the first anchoring element 16.1 that isas tension-free as possible over a large area. If the anchoring elements16.1, which are respectively anchored on the opposite edges of the wound12, are pulled toward one another by means of the threaded spindle 28,this leads to an asymmetrical stretching of the skin 10 on the edge ofthe wound 12 that is on the right-hand side in FIG. 8. In contrast, theopposing force for supporting the tensile force exerted by the anchoringelement 16.1 on the right-hand edge of the wound is distributed over alarge area of the skin by the first anchoring element 16.1 and thesubsequent anchoring elements 16.2 on the left-hand side of the wound inFIG. 8, such that virtually no tensile force is introduced into the skinthere by the individual anchoring elements 16.1, 16.2.

LIST OF REFERENCE CHARACTERS

-   10 Skin-   12 Wound-   14 Band-   16 Anchoring elements-   16.1 First anchoring element-   16.2 Second anchoring element-   18 Hook-   20 Transverse ribs-   22 Housing-   24 Locking tongue-   26 Handling tip-   28 Threaded spindle-   30 Threaded rods-   32 Head-   34 Threaded nut-   36 Screw pressure spring-   38 Screw pressure spring-   40 Bone

1. A device for stretching the skin, having at least one guide devicerunning in a stretching direction, having a pair of first anchoringelements that may be anchored in the skin and guided and disposed in amutually adjustable manner on the guide device in order to reduce anintermediate area between the first anchoring elements, and having atleast one second anchoring element that is disposed on the guide devicein an adjustable fashion outside of the intermediate area.
 2. The deviceaccording to claim 1, wherein the anchoring elements may be locked in areleasable manner on the guide device.
 3. The device according to claim1, wherein the guide device has a flexible band running in thestretching direction on which the anchoring elements are mounted in anadjustable and fixable fashion.
 4. The device according to claim 3,wherein the band comprises transverse ribs in which the anchoringelements may be locked.
 5. The device according to claim 1, wherein theguide device comprises at least one threaded spindle by means of whichthe anchoring elements are adjustable.
 6. The device according to claim1, wherein the first anchoring element and a subsequent second anchoringelement and/or two subsequent anchoring elements are connected to oneanother by means of threaded rods and are adjustable relative to oneanother by means of threaded nuts disposed on said threaded rods.
 7. Thedevice according to claim 1, wherein the anchoring elements may beanchored by means of hooks or safety needles that are insertable intothe skin.
 8. The device according to one of claim 1, wherein theanchoring elements are manually adjustable.
 9. The device according toone of claim 1, wherein the anchoring elements are adjustable in amotorized fashion.
 10. The device according to claim 9, wherein currentvalues of skin stretching are measured and a motorized adjustmentregulates these current values to target values that may bepredetermined.
 11. A method for stretching the skin using tensile forcesthat are introduced into the skin by means of anchoring elements thatare anchored in the skin and that are adjustable in their distance fromone another, wherein tensile forces that act in a same pulling directionand whose magnitude is adjustable independently from one another areintroduced into the skin at least two points offset relative to oneanother.
 12. The method according to claim 11, wherein the tensileforces are introduced at a distance of to 20 cm.
 13. The methodaccording to claim 11, wherein the tensile forces introduced at adistance from one another in the stretching direction are each less thanthe tensile force that would cause ischemia on a pressure side of theanchoring elements.
 14. The method according to claim 11, wherein atleast two anchoring elements are anchored in the skin in the samepulling direction in the stretching direction, in that a high degree oftensile force is introduced into the skin via at least one of theseanchoring elements and a low degree of tensile force is introduced intothe skin by at least one other of these anchoring elements, and suchthat introduction of high and low degrees of tensile force is cyclicallyswitched between these anchoring elements.
 15. The method according toclaim 14, the high degree of tensile force exceeds a value at whichischemia occurs on the pressure side of the anchoring element, and suchthat a low degree of tensile force allows the circulation of blood inthe tissue on the pressure side of the anchoring element.
 16. The methodaccording to claim 11, wherein a plurality of anchoring elementsdisposed one behind the other in the stretching direction are anchoredon one side of a wound in a large area of skin and a tensile force isintroduced into the skin in an asymmetrical fashion via the anchoringelements on an other side of the wound.
 17. The method according to oneof claim 11, wherein the tensile forces introduced into the skin may beadjusted manually.
 18. The method according to one of claim 11, whereinthe tensile forces introduced into the skin may be adjusted in amotorized fashion.
 19. The method according to claim 18, wherein thestretching of the skin is measured and the motorized adjustment of thetensile force is controlled in accordance with these measured values.20. The method according to claim 12, wherein the tensile forces areintroduced at a distance of approximately 1.5 to 3 cm.